#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main() {
	unordered_map<string, bool> vis;
	int n;
	cin >> n;
	string s;
	while (n--) {
		cin >> s;
		if (!vis.count(s))	vis[s] = 1;
	}
	cout << 52 - vis.size();
	return 0;
}
